I think it is entirely dependent on the situation.
From a health care point of view there are differences between, for want of a better word, races.
If you were to take an ECG of a normal healthy baby and do that every year it will gradually change into an adult ECG.
If the baby is white it will look like an adult ECG by the time the person is 20, if the person is black ie of African ancestry it can take until the person is 30.
Does that matter for education? Not a jot, but going into hospital with chest pain it matters.
I have no idea what the differences are between the ECGs of people who are first nations, Maori, Asian, SE Asian other ethnicity because there isn't much research.
If you are looking at educational achievement then it might be useful to both compare different groups and a white / not white because we are a white majority country, our education system was designed by and for white males.
I don't want to group people from numerous backgrounds together to sometimes it is a useful, if blunt, instrument.
On the other hand I have house shared with people from various backgrounds, some of whom have not fitted in the tick boxes because although one was Jamaican and the other African there were no boxes for 'white' under the Caribbean and African catagories.
On the other hand there are parts on UK where the kind of Christian you are matters more in terms of discrimination / non discrimination policies.